Organic light emitting diode (OLED for short) display screen has a characteristic of self-illumination, and uses a very thin coating of organic materials, which will emit light when energized, and a glass substrate. Furthermore, the OLED display screen has a large viewing angle and can significantly reduce the power consumption. Therefore the OLED display technology has found an increasingly wide application with the development of the display technology. For example, as an important application of the OLED display technology, an Active Matrix Organic Light Emitting Diode (AMOLED for short) display screen is widely used because of its features such as faster response speed, higher contrast, larger viewing angle and the like.
During the process of fabricating an OLED display screen, it is needed to use a packaging device to package a first substrate and a second substrate that have been prepared so as to form a display screen. The packaging device is an all-in-one packaging device with UV (ultra-violet) irradiation. The packaging device may comprise an upper quartz platform on which the second substrate may be arranged and a lower quartz platform on which a mask plate may be arranged, wherein the first substrate is arranged on the mask plate, and wherein the first substrate and the second substrate are packaged so as to form the display screen.
There are following technical problems in the prior art:
1) During the packaging process, it is necessary to align the first substrate by an alignment mechanism of mechanical fixing type and keep the first substrate being fixed on the mask plate after the alignment. However, the first substrate is easy to be deformed due to the stress produced by the aligning mechanism of mechanical fixing type which has a complicated structure.
2) It is necessary to align the first substrate on the mask plate by an alignment way of mechanical fixing type. However, the alignment mechanism of mechanical fixing type would interfere with the upper quartz platform in the subsequent process of pressing the first substrate and the second substrate together, resulting in the generation of bubbles between the first substrate and the second substrate and low alignment precision that would be ±7 μm generally.
3) If the alignment mechanism of mechanical fixing type is drawn back in the process of pressing, it would not interfere with the upper quartz platform. However, the first substrate is likely to slip off from the mask plate during the process of drawing back the alignment mechanism of mechanical fixing type.